The establishment always wins in the end.
McCain made nice but Giuliani and Romney drew more establishment support than McCain in 2008.
It's sort of a self fulfilling prophecy. Usually the GOP has a clear front-runner who dominates the early polling and wins in the end. In 2008, there was no overwhelming clear front-runner. But, Giuliani was ahead in the national polls in 2006-7 if I remember correctly.
But in 2016, there is no clear front-runner in my opinion. So, the history is not all that relevant.
Poll
